Course Pattern of the Muscular Branch of the Median Nerve in Sri Lankans Hand

Transligamentous variant of the recurrent motor branch is having a higher risk of getting damage during both endoscopic and open carpal tunnel releases. The incidence of the transligamentous variant is about 7% to 80% world wide. This wide variation of the incidence could be due to the failure of identification of the distal edge of the flexor retinaculum from the obliquely oriented fascia that runs from the distal edge. We used two criteria to identify the distal edge; the abrupt change in the thickness of the flexor retinaculum and its colour change in cross section. The incidence of transligamentous variant is rare and the reported high incidence could be due to an error in identification of the distal edge of the flexor retinaculum as shown by Kosin (1998).